Special Report Duncan Campbell has spent decades unmasking Britain's super-secretive GCHQ, its spying programmes, and its cosy relationship with America's NSA. Today, he retells his life's work exposing the government's over-reaching surveillance, and reveals documents from the leaked Snowden files confirming the history of the fearsome ECHELON intercept project.

Ever since legendary British investigative journalist Duncan Campbell told the world in a 1988 magazine article about ECHELON — a massive, automated surveillance dragnet that indiscriminately intercepted phone and Internet data from communications satellites — Western intelligence officials have refused to acknowledge that it existed.